Flat flexible cable (FFC) is typically made of a plastic substrate having a plurality of copper conductors or the like mounted or attached to the plastic substrate. Generally, the plastic substrate and copper conductor assembly is flat and flexible. The copper conductors can vary in width and thickness depending on the current carrying capacity requirements. Many types of plastic have been used to form the plastic substrate such as polypropylene, Mylar, polyurethane and the like. FFC has many advantages over the conventional round wire harnesses or assemblies. For example, FFC takes up less volume, weighs less and increases the robustness of the electronic assembly. Further, the cost of manufacturing FFC is lower than the cost of manufacturing round wire harnesses. FFC can be constructed in multiple layers and fit in very confined areas such as within an instrument panel or an engine compartment of a vehicle. Packaging of FFC within a vehicle is particularly important as vehicles have very limited space and the number of electronic packages and wire harnesses are increasing and competing for that limited space.
One significant problem confronting designers of FFC systems is that FFC is not structurally stable at soldering temperatures. Thus, FFC may not be easily soldered using conventional soldering methods. Such conventional soldering methods can damage the plastic insulating materials.
Therefore, there is a need for a new and improved system and method for interconnecting the conductors of an FFC. The method should not structurally damage the plastic insulating layer; however the method should provide a metallurgical interconnection between conductors of two adjoining FFCs.